/**
 * jQuery插件：图片剪裁
 * 
 * @author  imgAreaSelect
 * @url     http://odyniec.net/projects/imgareaselect/
 * @name    jquery.imareaselect.js
 * @since   2011-5-18 17:30:50
 */
(function($) {
    var abs = Math.abs,
    max = Math.max,
    min = Math.min,
    round = Math.round;
    function div() {
        return $('<div/>');
    }
    $.imgAreaSelect = function (img, options) {
        var
        $img = $(img),
        imgLoaded,
        $box = div(),
        $area = div(),
        $border = div().add(div()).add(div()).add(div()),
        $outer = div().add(div()).add(div()).add(div()),
        $handles = $([]),
        $areaOpera,
        left, top,
        imgOfs,
        imgWidth, imgHeight,
        $parent,
        parOfs,
        zIndex = 0,
        position = 'absolute',
        startX, startY,
        scaleX, scaleY,
        resizeMargin = 10,
        resize,
        minWidth, minHeight, maxWidth, maxHeight,
        aspectRatio,
        shown,
        x1, y1, x2, y2,
        selection = {
            x1: 0, 
            y1: 0, 
            x2: 0, 
            y2: 0, 
            width: 0, 
            height: 0
        },
        docElem = document.documentElement,
        $p, d, i, o, w, h, adjusted;
        function viewX(x) {
            return x + imgOfs.left - parOfs.left;
        }
        function viewY(y) {
            return y + imgOfs.top - parOfs.top;
        }
        function selX(x) {
            return x - imgOfs.left + parOfs.left;
        }
        function selY(y) {
            return y - imgOfs.top + parOfs.top;
        }
        function evX(event) {
            return event.pageX - parOfs.left;
        }
        function evY(event) {
            return event.pageY - parOfs.top;
        }
        function getSelection(noScale) {
            var sx = noScale || scaleX, sy = noScale || scaleY;
            return {
                x1: round(selection.x1 * sx),
                y1: round(selection.y1 * sy),
                x2: round(selection.x2 * sx),
                y2: round(selection.y2 * sy),
                width: round(selection.x2 * sx) - round(selection.x1 * sx),
                height: round(selection.y2 * sy) - round(selection.y1 * sy)
            };
        }
        function setSelection(x1, y1, x2, y2, noScale) {
            var sx = noScale || scaleX, sy = noScale || scaleY;
            selection = {
                x1: round(x1 / sx),
                y1: round(y1 / sy),
                x2: round(x2 / sx),
                y2: round(y2 / sy)
            };
            selection.width = selection.x2 - selection.x1;
            selection.height = selection.y2 - selection.y1;
        }
        function adjust() {
            if (!$img.width())
                return;
            imgOfs = {
                left: round($img.offset().left), 
                top: round($img.offset().top)
            };
            imgWidth = $img.width();
            imgHeight = $img.height();
            minWidth = options.minWidth || 0;
            minHeight = options.minHeight || 0;
            maxWidth = min(options.maxWidth || 1<<24, imgWidth);
            maxHeight = min(options.maxHeight || 1<<24, imgHeight);
            if ($().jquery == '1.3.2' && position == 'fixed' &&
                !docElem['getBoundingClientRect'])
                {
                imgOfs.top += max(document.body.scrollTop, docElem.scrollTop);
                imgOfs.left += max(document.body.scrollLeft, docElem.scrollLeft);
            }
            parOfs = $.inArray($parent.css('position'), ['absolute', 'relative']) + 1 ?
            {
                left: round($parent.offset().left) - $parent.scrollLeft(),
                top: round($parent.offset().top) - $parent.scrollTop()
            } :
            position == 'fixed' ?
            {
                left: $(document).scrollLeft(), 
                top: $(document).scrollTop()
            } :
{
                left: 0, 
                top: 0
            };
            left = viewX(0);
            top = viewY(0);
            if (selection.x2 > imgWidth || selection.y2 > imgHeight)
                doResize();
        }
        function update(resetKeyPress) {
            if (!shown) return;
            $box.css({
                left: viewX(selection.x1), 
                top: viewY(selection.y1)
            })
            .add($area).width(w = selection.width).height(h = selection.height);
            $area.add($border).add($handles).css({
                left: 0, 
                top: 0
            });
            $border
            .width(max(w - $border.outerWidth() + $border.innerWidth(), 0))
            .height(max(h - $border.outerHeight() + $border.innerHeight(), 0));
            $($outer[0]).css({
                left: left, 
                top: top,
                width: selection.x1, 
                height: imgHeight
            });
            $($outer[1]).css({
                left: left + selection.x1, 
                top: top,
                width: w, 
                height: selection.y1
            });
            $($outer[2]).css({
                left: left + selection.x2, 
                top: top,
                width: imgWidth - selection.x2, 
                height: imgHeight
            });
            $($outer[3]).css({
                left: left + selection.x1, 
                top: top + selection.y2,
                width: w, 
                height: imgHeight - selection.y2
            });
            w -= $handles.outerWidth();
            h -= $handles.outerHeight();
            switch ($handles.length) {
                case 8:
                    $($handles[4]).css({
                        left: w / 2
                    });
                    $($handles[5]).css({
                        left: w, 
                        top: h / 2
                    });
                    $($handles[6]).css({
                        left: w / 2, 
                        top: h
                    });
                    $($handles[7]).css({
                        top: h / 2
                    });
                case 4:
                    $handles.slice(1,3).css({
                        left: w
                    });
                    $handles.slice(2,4).css({
                        top: h
                    });
            }
            if (resetKeyPress !== false) {
                if ($.imgAreaSelect.keyPress != docKeyPress)
                    $(document).unbind($.imgAreaSelect.keyPress,
                        $.imgAreaSelect.onKeyPress);
                if (options.keys)
                    $(document)[$.imgAreaSelect.keyPress](
                        $.imgAreaSelect.onKeyPress = docKeyPress);
            }
            if ($.browser.msie && $border.outerWidth() - $border.innerWidth() == 2) {
                $border.css('margin', 0);
                setTimeout(function () {
                    $border.css('margin', 'auto');
                }, 0);
            }
        }
        function doUpdate(resetKeyPress) {
            adjust();
            update(resetKeyPress);
            x1 = viewX(selection.x1);
            y1 = viewY(selection.y1);
            x2 = viewX(selection.x2);
            y2 = viewY(selection.y2);
        }
        function hide($elem, fn) {
            options.fadeSpeed ? $elem.fadeOut(options.fadeSpeed, fn) : $elem.hide();
        }
        function areaMouseMove(event) {
            var x = selX(evX(event)) - selection.x1,
            y = selY(evY(event)) - selection.y1;
            if (!adjusted) {
                adjust();
                adjusted = true;
                $box.one('mouseout', function () {
                    adjusted = false;
                });
            }
            resize = '';
            if (options.resizable) {
                if (y <= resizeMargin)
                    resize = 'n';
                else if (y >= selection.height - resizeMargin)
                    resize = 's';
                if (x <= resizeMargin)
                    resize += 'w';
                else if (x >= selection.width - resizeMargin)
                    resize += 'e';
            }
            $box.css('cursor', resize ? resize + '-resize' :
                options.movable ? 'move' : '');
            if ($areaOpera)
                $areaOpera.toggle();
        }
        function docMouseUp(event) {
            $('body').css('cursor', '');
            if (options.autoHide || selection.width * selection.height == 0)
                hide($box.add($outer), function () {
                    $(this).hide();
                });
            options.onSelectEnd(img, getSelection());
            $(document).unbind('mousemove', selectingMouseMove);
            $box.mousemove(areaMouseMove);
        }
        function areaMouseDown(event) {
            if (event.which != 1) return false;
            adjust();
            if (resize) {
                $('body').css('cursor', resize + '-resize');
                x1 = viewX(selection[/w/.test(resize) ? 'x2' : 'x1']);
                y1 = viewY(selection[/n/.test(resize) ? 'y2' : 'y1']);
                $(document).mousemove(selectingMouseMove)
                .one('mouseup', docMouseUp);
                $box.unbind('mousemove', areaMouseMove);
            }
            else if (options.movable) {
                startX = left + selection.x1 - evX(event);
                startY = top + selection.y1 - evY(event);
                $box.unbind('mousemove', areaMouseMove);
                $(document).mousemove(movingMouseMove)
                .one('mouseup', function () {
                    options.onSelectEnd(img, getSelection());
                    $(document).unbind('mousemove', movingMouseMove);
                    $box.mousemove(areaMouseMove);
                });
            }
            else
                $img.mousedown(event);
            return false;
        }
        function fixAspectRatio(xFirst) {
            if (aspectRatio)
                if (xFirst) {
                    x2 = max(left, min(left + imgWidth,
                        x1 + abs(y2 - y1) * aspectRatio * (x2 > x1 || -1)));
                    y2 = round(max(top, min(top + imgHeight,
                        y1 + abs(x2 - x1) / aspectRatio * (y2 > y1 || -1))));
                    x2 = round(x2);
                }
                else {
                    y2 = max(top, min(top + imgHeight,
                        y1 + abs(x2 - x1) / aspectRatio * (y2 > y1 || -1)));
                    x2 = round(max(left, min(left + imgWidth,
                        x1 + abs(y2 - y1) * aspectRatio * (x2 > x1 || -1))));
                    y2 = round(y2);
                }
        }
        function doResize() {
            x1 = min(x1, left + imgWidth);
            y1 = min(y1, top + imgHeight);
            if (abs(x2 - x1) < minWidth) {
                x2 = x1 - minWidth * (x2 < x1 || -1);
                if (x2 < left)
                    x1 = left + minWidth;
                else if (x2 > left + imgWidth)
                    x1 = left + imgWidth - minWidth;
            }
            if (abs(y2 - y1) < minHeight) {
                y2 = y1 - minHeight * (y2 < y1 || -1);
                if (y2 < top)
                    y1 = top + minHeight;
                else if (y2 > top + imgHeight)
                    y1 = top + imgHeight - minHeight;
            }
            x2 = max(left, min(x2, left + imgWidth));
            y2 = max(top, min(y2, top + imgHeight));
            fixAspectRatio(abs(x2 - x1) < abs(y2 - y1) * aspectRatio);
            if (abs(x2 - x1) > maxWidth) {
                x2 = x1 - maxWidth * (x2 < x1 || -1);
                fixAspectRatio();
            }
            if (abs(y2 - y1) > maxHeight) {
                y2 = y1 - maxHeight * (y2 < y1 || -1);
                fixAspectRatio(true);
            }
            selection = {
                x1: selX(min(x1, x2)), 
                x2: selX(max(x1, x2)),
                y1: selY(min(y1, y2)), 
                y2: selY(max(y1, y2)),
                width: abs(x2 - x1), 
                height: abs(y2 - y1)
            };
            update();
            options.onSelectChange(img, getSelection());
        }
        function selectingMouseMove(event) {
            x2 = resize == '' || /w|e/.test(resize) || aspectRatio ? evX(event) : viewX(selection.x2);
            y2 = resize == '' || /n|s/.test(resize) || aspectRatio ? evY(event) : viewY(selection.y2);
            doResize();
            return false;
        }
        function doMove(newX1, newY1) {
            x2 = (x1 = newX1) + selection.width;
            y2 = (y1 = newY1) + selection.height;
            $.extend(selection, {
                x1: selX(x1), 
                y1: selY(y1), 
                x2: selX(x2),
                y2: selY(y2)
            });
            update();
            options.onSelectChange(img, getSelection());
        }
        function movingMouseMove(event) {
            x1 = max(left, min(startX + evX(event), left + imgWidth - selection.width));
            y1 = max(top, min(startY + evY(event), top + imgHeight - selection.height));
            doMove(x1, y1);
            event.preventDefault();
            return false;
        }
        function startSelection() {
            adjust();
            x2 = x1;
            y2 = y1;
            doResize();
            resize = '';
            if ($outer.is(':not(:visible)'))
                $box.add($outer).hide().fadeIn(options.fadeSpeed||0);
            shown = true;
            $(document).unbind('mouseup', cancelSelection)
            .mousemove(selectingMouseMove).one('mouseup', docMouseUp);
            $box.unbind('mousemove', areaMouseMove);
            options.onSelectStart(img, getSelection());
        }
        function cancelSelection() {
            $(document).unbind('mousemove', startSelection);
            hide($box.add($outer));
            selection = {
                x1: selX(x1), 
                y1: selY(y1), 
                x2: selX(x1), 
                y2: selY(y1),
                width: 0, 
                height: 0
            };
            options.onSelectChange(img, getSelection());
            options.onSelectEnd(img, getSelection());
        }
        function imgMouseDown(event) {
            if (event.which != 1 || $outer.is(':animated')) return false;
            adjust();
            startX = x1 = evX(event);
            startY = y1 = evY(event);
            $(document).one('mousemove', startSelection)
            .one('mouseup', cancelSelection);
            return false;
        }
        function windowResize() {
            doUpdate(false);
        }
        function imgLoad() {
            imgLoaded = true;
            setOptions(options = $.extend({
                classPrefix: 'imgareaselect',
                movable: true,
                resizable: true,
                parent: 'body',
                onInit: function () {},
                onSelectStart: function () {},
                onSelectChange: function () {},
                onSelectEnd: function () {}
            }, options));
            $box.add($outer).css({
                visibility: ''
            });
            if (options.show) {
                shown = true;
                adjust();
                update();
                $box.add($outer).hide().fadeIn(options.fadeSpeed||0);
            }
            setTimeout(function () {
                options.onInit(img, getSelection());
            }, 0);
        }
        var docKeyPress = function(event) {
            var k = options.keys, d, t, key = event.keyCode;
            d = !isNaN(k.alt) && (event.altKey || event.originalEvent.altKey) ? k.alt :
            !isNaN(k.ctrl) && event.ctrlKey ? k.ctrl :
            !isNaN(k.shift) && event.shiftKey ? k.shift :
            !isNaN(k.arrows) ? k.arrows : 10;
            if (k.arrows == 'resize' || (k.shift == 'resize' && event.shiftKey) ||
                (k.ctrl == 'resize' && event.ctrlKey) ||
                (k.alt == 'resize' && (event.altKey || event.originalEvent.altKey)))
                {
                switch (key) {
                    case 37:
                        d = -d;
                    case 39:
                        t = max(x1, x2);
                        x1 = min(x1, x2);
                        x2 = max(t + d, x1);
                        fixAspectRatio();
                        break;
                    case 38:
                        d = -d;
                    case 40:
                        t = max(y1, y2);
                        y1 = min(y1, y2);
                        y2 = max(t + d, y1);
                        fixAspectRatio(true);
                        break;
                    default:
                        return;
                }
                doResize();
            }
            else {
                x1 = min(x1, x2);
                y1 = min(y1, y2);
                switch (key) {
                    case 37:
                        doMove(max(x1 - d, left), y1);
                        break;
                    case 38:
                        doMove(x1, max(y1 - d, top));
                        break;
                    case 39:
                        doMove(x1 + min(d, imgWidth - selX(x2)), y1);
                        break;
                    case 40:
                        doMove(x1, y1 + min(d, imgHeight - selY(y2)));
                        break;
                    default:
                        return;
                }
            }
            return false;
        };
        function styleOptions($elem, props) {
            for (option in props)
                if (options[option] !== undefined)
                    $elem.css(props[option], options[option]);
        }
        function setOptions(newOptions) {
            if (newOptions.parent)
                ($parent = $(newOptions.parent)).append($box.add($outer));
            $.extend(options, newOptions);
            adjust();
            if (newOptions.handles != null) {
                $handles.remove();
                $handles = $([]);
                i = newOptions.handles ? newOptions.handles == 'corners' ? 4 : 8 : 0;
                while (i--)
                    $handles = $handles.add(div());
                $handles.addClass(options.classPrefix + '-handle').css({
                    position: 'absolute',
                    fontSize: 0,
                    zIndex: zIndex + 1 || 1
                });
                if (!parseInt($handles.css('width')) >= 0)
                    $handles.width(5).height(5);
                if (o = options.borderWidth)
                    $handles.css({
                        borderWidth: o, 
                        borderStyle: 'solid'
                    });
                styleOptions($handles, {
                    borderColor1: 'border-color',
                    borderColor2: 'background-color',
                    borderOpacity: 'opacity'
                });
            }
            scaleX = options.imageWidth / imgWidth || 1;
            scaleY = options.imageHeight / imgHeight || 1;
            if (newOptions.x1 != null) {
                setSelection(newOptions.x1, newOptions.y1, newOptions.x2,
                    newOptions.y2);
                newOptions.show = !newOptions.hide;
            }
            if (newOptions.keys)
                options.keys = $.extend({
                    shift: 1, 
                    ctrl: 'resize'
                },
                newOptions.keys);
            $outer.addClass(options.classPrefix + '-outer');
            $area.addClass(options.classPrefix + '-selection');
            for (i = 0; i++ < 4;)
                $($border[i-1]).addClass(options.classPrefix + '-border' + i);
            styleOptions($area, {
                selectionColor: 'background-color',
                selectionOpacity: 'opacity'
            });
            styleOptions($border, {
                borderOpacity: 'opacity',
                borderWidth: 'border-width'
            });
            styleOptions($outer, {
                outerColor: 'background-color',
                outerOpacity: 'opacity'
            });
            if (o = options.borderColor1)
                $($border[0]).css({
                    borderStyle: 'solid', 
                    borderColor: o
                });
            if (o = options.borderColor2)
                $($border[1]).css({
                    borderStyle: 'dashed', 
                    borderColor: o
                });
            $box.append($area.add($border).add($handles).add($areaOpera));
            if ($.browser.msie) {
                if (o = $outer.css('filter').match(/opacity=([0-9]+)/))
                    $outer.css('opacity', o[1]/100);
                if (o = $border.css('filter').match(/opacity=([0-9]+)/))
                    $border.css('opacity', o[1]/100);
            }
            if (newOptions.hide)
                hide($box.add($outer));
            else if (newOptions.show && imgLoaded) {
                shown = true;
                $box.add($outer).fadeIn(options.fadeSpeed||0);
                doUpdate();
            }
            aspectRatio = (d = (options.aspectRatio || '').split(/:/))[0] / d[1];
            $img.add($outer).unbind('mousedown', imgMouseDown);
            if (options.disable || options.enable === false) {
                $box.unbind('mousemove', areaMouseMove).unbind('mousedown', areaMouseDown);
                $(window).unbind('resize', windowResize);
            }
            else {
                if (options.enable || options.disable === false) {
                    if (options.resizable || options.movable)
                        $box.mousemove(areaMouseMove).mousedown(areaMouseDown);
                    $(window).resize(windowResize);
                }
                if (!options.persistent)
                    $img.add($outer).mousedown(imgMouseDown);
            }
            options.enable = options.disable = undefined;
        }
        this.remove = function () {
            $img.unbind('mousedown', imgMouseDown);
            $box.add($outer).remove();
        };
        this.getOptions = function () {
            return options;
        };
        this.setOptions = setOptions;
        this.getSelection = getSelection;
        this.setSelection = setSelection;
        this.update = doUpdate;
        $p = $img;
        while ($p.length) {
            zIndex = max(zIndex,
                !isNaN($p.css('z-index')) ? $p.css('z-index') : zIndex);
            if ($p.css('position') == 'fixed')
                position = 'fixed';
            $p = $p.parent(':not(body)');
        }
        zIndex = options.zIndex || zIndex;
        if ($.browser.msie)
            $img.attr('unselectable', 'on');
        $.imgAreaSelect.keyPress = $.browser.msie ||
        $.browser.safari ? 'keydown' : 'keypress';
        if ($.browser.opera)
            $areaOpera = div().css({
                width: '100%', 
                height: '100%',
                position: 'absolute', 
                zIndex: zIndex + 2 || 2
            });
        $box.add($outer).css({
            visibility: 'hidden', 
            position: position,
            overflow: 'hidden', 
            zIndex: zIndex || '0'
        });
        $box.css({
            zIndex: zIndex + 2 || 2
        });
        $area.add($border).css({
            position: 'absolute', 
            fontSize: 0
        });
        img.complete || img.readyState == 'complete' || !$img.is('img') ?
        imgLoad() : $img.one('load', imgLoad);
    };
    $.fn.imgAreaSelect = function (options) {
        options = options || {};
        this.each(function () {
            if ($(this).data('imgAreaSelect')) {
                if (options.remove) {
                    $(this).data('imgAreaSelect').remove();
                    $(this).removeData('imgAreaSelect');
                }
                else
                    $(this).data('imgAreaSelect').setOptions(options);
            }
            else if (!options.remove) {
                if (options.enable === undefined && options.disable === undefined)
                    options.enable = true;
                $(this).data('imgAreaSelect', new $.imgAreaSelect(this, options));
            }
        });
        if (options.instance)
            return $(this).data('imgAreaSelect');
        return this;
    };
})(jQuery);